Ibanez SD9 distortion oscillating

[omortier]

Hi there.
I own a ibanez SD9 green pedal. I really love the sound of that pedal, but I've an oscillation problem when it is powered from an AC to DC adaptor.
A real hi frq is generated. I've read somewhere that a 1000 Ma adaptor may be too much and may be the reason why it is oscillating.
Any idea, I'm stuck?

thanks

 

[Andronico]

The Mamps of the AC-DC power supply don´t produce the oscillation. If the pedal works well with a battery, the problem is that the AC-DC adaptor is not regulated or is poorly filtered or both. Is very important that the adaptor you use for your pedals will be a good quality one.

General Guitar Gadgets has these DIY projects :

http://www.generalguitargadgets.com/index.php?option=com_content&task=view&id=135&Itemid=26

http://www.generalguitargadgets.com/index.php?option=com_content&task=view&id=134&Itemid=26

Hope that helps

 

[unclejed613]

my guess would be dried out filter caps in the wall wart if it even has any. the filter caps on these little pains-in-the-neck dry out rather quickly, since wall warts are usually made with no cooling slots and they spend a lot of time plugged in generating internal heat, even when they're not being used.

 

[Brion55]

Some so-called "DC" wall warts have rectification only and little or no filtering. Might try putting a 100mfd electrolytic and .01 parallel to it from B+ to ground in the pedel to see if that shuts it up.

 

[omortier]

Thanks for your comments.
I've tried with differents AC/DC adaptor, all my otehrs pedals are fine with the PSU I use with my true bypass system.
I think that effectivelly, my next step will be to change the electrolytic Caps. The trouble is that all the schematics I've found on that pedal (PCB MP-SD 1301A) are not corresponding to the components list and looks only modded things.
If someone has the schem, it would be really cool.
regards

 

[Minion]

You can simply Solder a 100uF Cap across the +v terminal to the Ground terminal and there you have extra PSU Filtering, You could probably solder it directly on the Pedals Power input jack or on the bottom of the PCB at the power input....